5-year-old Summa Cum Boom is dead after breaking down near the quarter pole of yesterday’s 3rd race at Parx. For this mostly career claimer, oblivion. The complicit: jockey Jacqueline Davis, who rode Caillech’s Quest to premature death on Sunday; trainer J Guadalupe Guerrero; owner John Loyle; breeder Ascoli Piceno Stables; and all prior connections. A note: In his penultimate start on April 22nd at Parx, Summa Cum Boom finished last of nine, some 15 lengths back. Going – and gone.